# CVE-2026-13538: Wavlink WL-NU516U1-A POST Parameter wireless.cgi sub_401D68 command injection

> Remote attackers can execute arbitrary commands via crafted POST parameters in the wireless configuration interface of Wavlink routers.

- **Severity:** Medium 5.3 (`CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:L/VI:L/VA:L/SC:N/SI:N/SA:N/E:P`)
- **Exploited in the wild:** Not known
- **Login needed:** Any signed-in user
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 29 Jun 2026
- **Updated:** 29 Jun 2026
- **Also known as:** GHSA-ffh8-39gq-j894

## What is CVE-2026-13538?

CVE-2026-13538 is a medium-severity command injection vulnerability in Wavlink WL-NU516U1-A, published on 29 Jun 2026. Any signed-in user can exploit it over the network, with no action from the victim.

### Official description

A vulnerability was determined in Wavlink WL-NU516U1-A M16U1_V240425. The affected element is the function sub_401D68 of the file /cgi-bin/wireless.cgi of the component POST Parameter Handler. This manipulation of the argument SSID2G2/SSID5G2/AuthMethod2/WPAPSK12 causes command injection. Remote exploitation of the attack is possible. The exploit has been publicly disclosed and may be utilized. The affected component should be upgraded. The vendor was contacted early, responded in a very professional manner and quickly released a fixed version of the affected product.

Weakness: CWE-77 (Improper Neutralization of Special Elements used in a Command), CWE-74 (Improper Neutralization of Special Elements in Output Used by a Downstream Component)

## Which versions are affected by CVE-2026-13538?


## How do I fix CVE-2026-13538?

No fix has been published for CVE-2026-13538 yet. Limit exposure of the affected software until one is available.

## Is CVE-2026-13538 being exploited?

It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-13538 exists.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-13538 and fix it if it is affected.

What it is: CVE-2026-13538 is a medium-severity command injection vulnerability in Wavlink WL-NU516U1-A, published on 29 Jun 2026. Any signed-in user can exploit it over the network, with no action from the victim.
Exploitation: It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-13538 exists.

Affected product: Wavlink WL-NU516U1-A. No package-level version data is available, so check the vendor advisory linked from the reference page.

Task:
1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.
2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.
3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.
4. Run the tests and summarise what changed and why.
5. If nothing in the project is affected, say so and change nothing.

Reference: https://insights.sbomify.com/CVE-2026-13538/ (Markdown: https://insights.sbomify.com/CVE-2026-13538/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-13538
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-13538
- OSV: https://osv.dev/vulnerability/CVE-2026-13538

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-13538/
Summaries are generated and may contain mistakes; the official description above is the record.